Sheet metal clamp operating tool



April 29, 1952 Filed Feb. 19, 1949 W. L. LINCOLN SHEET METAL CLAMPOPERATING TOOL FIG.

WYLY

V nu! Zul-l 2 sl-lEETs-SHEET 1 INVENToR S l.. LINCOLN BEM/"MMM ATTORNEYSApril 29, 1952 w. L. LINCOLN SHEET METAL CLAMP OPERATING TooE 2SHEETS-SHEET 2 Filed Feb. 19, 1949 FIG. 3.

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INVENTOR WYLYS L. LINCOLN BY mw M ATTORNEYS Patented Apr. 29, 1952UNITED STATES PATENT OFFICE SHEET METAL CLAMP OPERATING TOOL ApplicationFebruary 19, 1949, Serial No. 77,312

4 Claims. l

This invention relates to improvements in pliers-like tools used foroperating spring loaded sheet metal clamps and the like.

Sheet metal clamps of the type most generalll used are shown, forinstance, by United States Letters Patent 2,266,929. Briefly described,they comprise a tubular body having a reduced opening at its outer end,and one or more spring loaded clamping pins are mounted in the bodi7 toreciprocate through the reduced opening, the outer ends of the pinshaving lateral projections to engage a work sheet adjacent a perforationin the sheet through which the pins are inserted. A coil spring aroundthe pins urges them retracted. To protract the pins preparatory toinserting them in a hole in a work sheet to be clamped, it

`is necessary to use a tool to overcome the retractive pressure of thespring. While there are gun type tools for this purpose which move thepins in a direction truly axially of the clamp body, the tool mostcommonly used is a pliers-like clamp tool which is much lighter inweight, less bulky and more economical. However, all the pliers-liketools of which I am aware have the shortcoming that they tend tobend theclamp pins in an arc because the jaws necessarily move in an arc. Thistends to deform and distort the clamp pins.

It is an object of this invention to overcome those dilliculties andshortcomings of the plierslike clamp operating tool and to provide atool of this type which maintains the clamp and its parts in straightand unbent condition throughout the clamp compressing movement of thejaws of the tool.

It is another object of my invention to provide a sheet metal clampoperating tool of the plierslike type which does not tend to deform ordistort the clamp.

Other objects which are more or less subordinate to the above statedobjects will become apparent from the following description of onespecic construction embodying the invention,

' for which purpose I shall refer to the yaccompanying drawings, inwhich:

Fig. 1 is a view partly in side elevation and partly in section of atool embodying one adaptation of my invention;

Fig. 2 is an enlarged fragmentary view, partly in side elevation andpartly in section, showing the device of Fig. 1 in clamp-compressingposition, a portion of the lower jaw being broken off, and the clampbeing shown in broken lines;

Fig. 3 is a view similar to Fig. 2 but showing the tool at the sta-rt ofthe clamp-compressing operation;

l partly in section of a modified form of device.

-Referring now to the drawings, Figs. 1-5, the tool is generally denotedby the numeral 5 and has an upper jaw 6 and a lower jaw 1 pivotallyconnected together by pin 8 for pliers-like swinging movement relativeto each other.

The jaws have handle portions 6a, la, respectively, so as to beconveniently operated by one hand.

Upper jaw 6 has a transverse hole IB adjacent its front end, in whichhole a stud l2 ts, the stud having an enlarged exteriorly threadedportion |2a, having its top end peened at 12b to prevent axial movementin the hole, and having a portion [2c depending from the threadedportion.

A clamp engaging sleeve-like member I5 has an axial bore to receiveportions I2a and |20 of the stud, and is interiorly threaded to receivethe portion I2a. The lower end of the member I5 is provided with arecess dened by the spherical surface I6. For diierent sized clamps itis therefore a simple matter to remove one member l5 Iand substituteanother for it on the tool.

The lower jaw 'l is forked lat its outer end and provides an arcuateclamp engaging shoulder 20, the shoulder being recessed in thejaw belowthe top surface 2l. While the side wall 2m of the upper half of the jawis curved to fairly closely receive the round body portion a of a sheetmetal clamp C, the outer ends 2 lb of the side walls 2 la are spacedapart a distance slightly less than the diameter of portion a of theclamp body, so that the clamp may not accidentally escape from the jaw.That is, in order to remove the clamp, it must be lifted upwardly fromthe cradle provided by the jaw until portion a is above the plane 2i ofthe top of the jaw.

For -the purposes to be described, the shoulder has diametricallyopposite high points 20a from which the'surface of the shoulder anglesdownwardly towards its ends about 9 from the high points 20a, being thepoints at which the shoulder is engaged by the annular shoulder b of theclamp. Also, the back portion 2|c of the side wall 2l a angles or flaresupwardly* and outwardly about .9", while the back portion 25a of theinner side wall of the lower half 25 of the jaw angles or ilaresdownwardly and outwardly, all as best seen in Figs. l and 2.

4It will be seen that the angular surfaces 2|c Yand 25a permit the clampbody to rock backwardly and forwardly on the pivotal point formed by thehigh points 20a of the shoulder.

The member l5 and stud l2 provide a depending projection from the upperjaw which renders it unnecessary to swing the upper jaw fartherdownwardly than as shown in Fig. 2 in order to fully compressthe clamp.In other words, if the jaws were swung farther together than shown inFig. 2, they would tend to bend the clamp C about an inward arc, whichis rendered unnecessary by the projection.

Starting with the position of Fig. 3, it will be seen that the clamprests against angular surface 2Ic and that the top end of theclamp isnot centered in the recess I6. As the jaws swing towards each other fromthat position, the `top end of the clamp moves along the sphericalsurface I6 until it becomes centered, and in the course of the swingingmovement of the jaws towards each other, the .clamp is -free to pivot`on the point 20a by virtue of the angular surfaces 2Ic and 25a, so thatat all times the clamp is held straight while its spring is lbeing com-lpressed.

In Fig. 6 I show a modified form of the invention in which the parts areas before described excepting only that in lieu of the .separateelements I2 and l5 being assembled in the upper jaw, they form integralparts thereof. For instance, the jaw 6 has an integral projection I5presenting a spherical recess I6 to engage the inner end of the clampbeing operated.

I find that by using my clamp operating tool, in comparison with othertools, lsheet metal clamps last considerably longer.

I claim:

1. In a tool for -holding and operating asheet metal clamp, a pair ofopposed jaws having handle portions, means pivoting the jaws togetherfor relative swinging movement about an axis transverse of the jaws, oneof the jaws having a pair of transversely spaced clamp engagingshoulders facing the other jaw, said shoulders having a pair oftransversely spaced, transversely alined relatively high pointsprojecting toward the other jaw, about which high points said clamp mayrock; and the other jaw being disposed to engage an opposite portion ofsaid clamp.

2. In a tool for holding and operating a sheet metal clamp having anelongated housing and a longitudinally outwardly facing,radially'extending shoulder on said housing, a pair of opposed jawshaving handle portions, the jaws lbeingpivotally connected togetherbetween their ends for pliers-like swinging movement relative -to eachother, a rst one of the jaws being bifurcated, the centrally facingwallsof the bifurcations being stepped to form a shoulder surface at adistance above the lower edges of said walls, said shoulder surfacefacing inwardly toward the other jaw for engaging lthe said outwardlyfacing clamp housing shoulder, said inwardly facing shoulder surfacepresenting substantially diametrically opposite localized areaswhich-are `relatively nearer the second jaw and which are disposed on aline across the space between the bifurcations of the first jaw, saidline being substantially parallel to the axis of said pivot, and aboutwhich localized areas said engaged clamp may rock, and the other jawbeing disposed to engage the inner portion 4of said clamp.

3. The combination as described in claim 2, in which the centrallyfacing walls of the bifurcations above the shoulder flare slightlyupwardly and divergingly at an angle which increases from zero, in eachdirection from the localized areas,

as the-distance from the said localized areas in- -crea-ses, and thesurface of the shoulder extend- `ing -in either direction from thelocalized areas lies in a plane embracing the localized areas which isat a slight angle to the axis of the jaw so that the surface of theshoulder extends deeper into the body of the jaw, whereby a support isprovided for the shoulder on the clamp housing in either of the twodirections of its lrocking movement.

4. In a tool for holding and operating ya sheet metal clamp, having anelongated housingfand an outwardly facing, radially extending shoulderon said housing, a pair of opposed jaws having handle portions, the jawsbeing pivotally connected together between their ends for-pliers-{likeswinging movement relative to each other, a rst one of the jaws beingbifurcated in the form of an interrupted ring, the centrally facingwalls of the bifurcations being stepped-to form an-arcuate shouldersurface at a distance above thevlower edges of said walls, said shouldersurface `facing inwardly toward the other jaw for'engaging the saidoutwardly facing clamp housing shoulder, said inwardly facing shouldersurface having an outside bounding diameter greater than the openingbetween the ends of the bifurcations and presenting substantiallydiametrically opposite vlocalized areas which arefrelatively nearer thesecond 'jaw and which are disposed on-a diametric line across theopening between the bifurcations of the first jaw,saidline beingsubstantially-parallel tothe axis of said `pivot and about whichlocalized vareas said engagedclamp may rock,said second jaw having aprojection extending toward the rst jaw, said projection having aconcave spherical end surface facing the first jaw `for engaging theinner end of the clamp and facilitating said 'rocking movement.

WYLYS vL. LINCOLN.

REFERENCES CITED The following references are of Yrecord in -the lc ofthis patent:

UNITED STATES PATENTS Number Name Date 1,536,241 vSuoka V May 5, 19252,328,866 Van Sittert et al. Sept. '7, 1943 2,352,722 Lipp July 4,l1944: 2,478,881 Wayryne'n Aug. 9, 1949

